ABSTRACT
The acute phase responses of an organism are the mechanisms by which it both defends itself and recovers from noxious insults. The hepatic component of the acute phase response is a major alteration in the expression of a subset of plasma proteins. Numerous studies on the biosynthesis of fibrinogen using a variety of experimental systems from animals undergoing an acute phase response to primary heptocyte cultures and hepatocarcinoma cells all reveal that interleukin-6 is the cytokine that controls the increase in fibrinogen gene expression. An elegant system has evolved for the regulated dissolution of the fibrin/platelet matrix following wound stabilization, and the fibrinogen/fibrin molecule is involved in the regulatory processes. A common feature of the agents that initiate the expression of functional fibrinogen receptors is that all are released at a vascular injury. In the truest sense, fibrinogen functions as a ligand in cell-to-cell attachment complexes.
